Pieces of aluminum or other metals can be melted by placing a load of the metal pieces in a furnace, and by firing burners so that the burner output impinges on the load. The melting process proceeds in two phases. In the first phase, gradual melting causes a molten bath to form and rise at the bottom of the load. Solid pieces of metal become submerged as the melting load descends into the rising molten bath. This is followed by the second phase of the process, in which the burners continue to fire into the space above the molten bath after the load becomes fully submerged. This provides heat that must be transferred to the submerged solids to ensure that the entire load becomes melted.